MCP14E5T-E/SL Microchip Technology, MCP14E5T-E/SL Datasheet - Page 13

• Manufacturer Part Number: MCP14E5T-E/SL
• Description: 4.5A Dual MOSFET Drvr 16 SOIC .150in T/R
• Manufacturer: Microchip Technology

Specifications of MCP14E5T-E/SL

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

TABLE 4-1:
FIGURE 4-3:
4.4
Careful layout and decoupling capacitors are highly
recommended when using MOSFET drivers. Large
currents are required to charge and discharge
capacitive loads quickly. For example, 2.5A are needed
to charge a 2200 pF load with 18V in 16 ns.
To operate the MOSFET driver over a wide frequency
range with low supply impedance, a ceramic and low
ESR film capacitor are recommended to be placed in
parallel between the driver V
ESR film capacitor and a 0.1 µF ceramic capacitor
should be used. These capacitors should be placed
close to the driver to minimized circuit board parasitics
and provide a local source for the required current.
4.5
Proper PCB layout is important in a high current, fast
switching circuit to provide proper device operation and
robustness of design. PCB trace loop area and
inductance should be minimized by the use of ground
planes or trace under MOSFET gate drive signals,
separate analog and power grounds, and local driver
decoupling.
© 2007 Microchip Technology Inc.
ENB_A
5V
ENB_x
0V
V
OUT x
0V
DD
H
H
H
H
L
Decoupling Capacitors
PCB Layout Considerations
ENB_B
H
H
H
H
L
ENABLE PIN LOGIC
V
EN_H
10%
t
D3
Enable Timing Waveform.
IN A
V
DD
H
H
L
L
X
EN_L
t
and GND. A 1.0 µF low
D4
90%
MCP14E3/MCP14E4/MCP14E5
IN B
H
H
X
L
L
OUT A
H
H
L
L
L
MCP14E3
OUT B
Placing a ground plane beneath the MCP14E3/
MCP14E4/MCP14E5 will help as a radiated noise
shield as well as providing some heat sinking for power
dissipated within the device.
4.6
The total internal power dissipation in a MOSFET driver
is the summation of three separate power dissipation
elements.
EQUATION 4-1:
4.6.1
The power dissipation caused by a capacitive load is a
direct function of frequency, total capacitive load, and
supply voltage. The power lost in the MOSFET driver
for a complete charging and discharging cycle of a
MOSFET is:
EQUATION 4-2:
H
H
L
L
L
Where:
Where:
P
V
P
P
CC
C
P
DD
Q
T
L
T
Power Dissipation
f
OUT A
CAPACITIVE LOAD DISSIPATION
H
H
L
L
L
MCP14E4
P
=
=
=
=
=
=
=
P
T
L
=
=
Total power dissipation
Load power dissipation
Quiescent power dissipation
Operating power dissipation
Switching frequency
Total load capacitance
MOSFET driver supply voltage
OUT B
P
f C
L
×
H
H
L
L
L
+
P
T
Q
×
+
V
OUT A
DD
P
H
H
L
L
L
DS22062A-page 13
CC
MCP14E5
2
OUT B
H
H
L
L
L